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In this study, we compared the polyphenolic composition of the roasted grapevine wood chips of four Vitis vinifera cultivars—namely, Sorbara, Grasparossa, Malbo Gentile, and Spergola. These waste byproducts have the potential as infusion chips for the aging of alcoholic beverages and vinegars, contributing to an enriched sensory profile. Roasting amplifies aromatic nuances and triggers the depletion of crucial bioactive compounds, including polyphenols. We investigated the extent of polyphenolic loss in the ethanolic extract of roasted grapevine chips to repurpose this waste byproduct and assess its potential. We assessed the levels of trans-resveratrol, trans-ε-viniferin, trans-piceatannol, and the main resveratrol trimer. Our findings indicated a significant decrease in polyphenol content as the roasting temperature increased, from 16.85–21.12 mg GAE/g for grapevine chips roasted at 120 °C to 3.10–7.77 mg GAE/g for those roasted at 240 °C. This study also highlights notable genotypic differences in polyphenolic content. Among the red grape cultivars analyzed, Sorbara exhibited the highest levels (7.77–21.12 mg/GAEg), whereas the white grape cultivar Spergola showed the lowest polyphenolic content (3.10–16.85 mg/GAEg). These findings not only contribute to the scientific understanding of polyphenol stability but also hold practical implications for the enhancement of aged beverages, as well as advancing sustainable practices in the viticulture industries. [ABSTRACT FROM AUTHOR]

This study aimed to compare the aroma profiles of Sorbara and Spergola grapevine prunings roasted at different temperatures (120, 140, 160, 180, 200, and 240 °C). One potential application of grapevine prunings is their use as infusion chips to enhance and improve the aging processes of alcoholic beverages and vinegars. Aromatic compounds impart unique flavors and contribute to the complexity of the final products. Thermogravimetry–mass spectrometry coupled with evolved gas analysis (TGA-MS-EGA) was conducted to identify the thermal steps at which substantial changes occurred in the wood matrix. Solid-phase microextraction–gas chromatography–mass spectrometry (SPME-GC-MS) was used for the analysis of volatile compounds. Several key volatile compounds were identified, showing variations in their concentrations as a function of cultivar and roasting temperature. Furan derivatives, such as furfural, and phenolic compounds, such as guaiacol and vanillin, were the two main chemical classes of volatile compounds that predominantly defined the aroma of grapevine chips roasted above 180 °C. At lower roasting temperatures, some aldehydes, such as hexanal and terpenes, defined the aroma profiles of the samples. By repurposing waste materials, this application offers a pathway for environmentally conscious viticulture and sustainable practices within the food industry. [ABSTRACT FROM AUTHOR]

Pruning canes from grape vines are valuable byproducts that contain resveratrol and other health-boosting stilbenoids. This study aimed to assess the effect of roasting temperature on the stilbenoid content of vine canes by comparing two Vitis vinifera cultivars, Lambrusco Ancellotta and Salamino. Samples were collected during different phases of the vine plant cycle. One set was collected in September after the grape harvest and was air-dried and analyzed. A second set was obtained during vine pruning in February and evaluated immediately after collection. The main stilbenoid identified in each sample was resveratrol (~100–2500 mg/kg), with significant levels of viniferin (~100–600 mg/kg) and piceatannol (~0–400 mg/kg). Their contents decreased with increasing roasting temperature and residence time on the plant. This study provides valuable insights into the use of vine canes in a novel and efficient manner, which could potentially benefit different industries. One potential use involves the roasted cane chips to accelerate the aging of vinegars and alcoholic beverages. This method is more efficient and cost-effective than traditional aging, which is slow and unfavorable from an industrial perspective. Furthermore, incorporating vine canes into maturation processes reduces viticulture waste and enhances the final products with health-promoting molecules, such as resveratrol. [ABSTRACT FROM AUTHOR]

In this study, the trend of VOCs of dietary fiber samples, coming from three different watermelon cultivars Citrullus lanatus L. (variety Gavina®®, Crimson Sweet, and Asahi Miyako) was investigated. This foodstuff, obtained as a by-product of residual agri-food production, has gained increasing attention because of its many bioactive components and high dietary fiber content. The result is a fibrous material for specific applications in food manufacturing, such as corrector for some functional and technological properties. In this study, a method based on headspace solid-phase microextraction (HS-SPME) coupled with gas chromatography–mass spectrometry (GC–MS) was used to characterize the aromatic profiles of the dried raw materials. Therefore, the VOCs of the samples of the three cultivars were investigated. Experimental results have shown that watermelon fibers generate VOCs, which can be grouped into six common classes of analytes. The different distributions of the identified compounds made it possible to effectively differentiate the three cultivars studied based on their peculiar aroma profiles. In particular, Gavina®® fiber is distinguished by the high content of terpenes, Asahi Miyako by the presence of aldehydes generated as fatty acid metabolites, and Crimson Sweet by the higher content of acetyl esters. [ABSTRACT FROM AUTHOR]